Method and apparatus for treating petroleum hydrocarbons



' Malfh 15 1927 w. M. cRoss- METHODl AND ArPARATUs Fon TREATINGPETROLEUM HYDRoGARBoNs Filed Nov. 24. 1924 fess; y 'I l l lPatented.Mar. 15, 1927.

UNITED STATES WALTER M. CROSS, OF KANSAS CITY,4MISSOURI.

METHOD AND APPARATUS FR TRATING PETROLEUM HYDBOCARBONS.

Application' led November 24, 1924. Serial No. 751,849.

This invention relates to improvements in a process and apparatus fortreating petroleum hydrocarbons, and refers more particularly to aprocess in which the hydrocarbons are subjected to an acid treatment anda subsequent treatment with clay alone or in combination with a metallicsalt in order to remove from the hydrocarbons such objectionableimpurities' as gums, resinous and sulphur compounds, some of which aredifcult to eliminate without rather complete treatment and with anattendent loss of considerable quantities of the oil and' treatingmaterials.

The advantages in the present process lie particularly in theeffectiveness of the treat.-

ment, the continuity of operation, the resulting product passing all ofthe well known tests such as the doctor tests, the copper corrosiontest, and test for percentages of gum or resinous material remaining inthe oil after treatment. f

The process also reduces considerably the time of treatment and theamount of treating materials utilized and aords a process by means ofwhich the ingredients recovered after treatment may be reused forsubsequent treatment; of hydrocarbons.

The single ligure is a diagrammatic elevational view of the apparatuswith parts in section.

The hydrocarbon to` be treated is introduced through the line 1controlled by a valve 2, while an acid material, preferablysulphuric-acid, is combined therewith, vbeing introduced through a line3 regulated by a valve 4. The mixture is charged, by means of a pump 5suitably constructed so as not to be attacked by the acid, through aline 6 `at the end of which is positioned a homogenizing valve showndiagrammatically at 7. The function ofl this valve is to separate anddivide the particles of the combined liquids into a spray or mistinducing a combination of the particles which is much more intimate thancan be obtained by agitation or mechanical mixing devices. Thehomogenized mixture passes through a tube 8 in which are positioned aplurality of vanes arranged in reverse directions in order yto producestill further turbulency and more intimate contact of the liquid. Themixture is then passed through the pipe l0 and is discharged through adivided pipe 11 into a centrifuge 12. The centrifuge is mounted uponbearing members 13 carried by supports 14 and rotated at high speed byvmeans of a.` motor 15 driving the pulleys vlo and 17 by means of a belt18. A gland connection 19 is positioned between the stationary tube 8and the rotating shaft 20 of the centrifuge.

The effect of the centrifuge is to separate the lighter oil from theheavier acid, the latter being thrown to the outer portion of therevolving centrifuge, while the lighter material will remain near thecenter thereof. Stationary outlet lines 21 extend practically to thecircumference of the inner surface of the centrifuge and serve towithdraw the heavier acid from the interior of the revolving separatingelement. Near the center of the centrifuge is a discharge'line 22 forremoving the lighter oil. The oil withdrawn through the line 22 isdischarged into a receptacle 23 and passes down through the line 24tothe agitator25. The acidtaken ofi' through the lines 21 is withdrawnthrough the line 26 from which it may be returned to1 the line 3 forreuse with the incoming o1 rlhe acid treated oil collecting in theagitator has introduced thereto a highly adsorbent hydrated silica clayof aluminum silicate such as bentonite or innumerable other clays of ahighly vadsorbent nature. rlhis clay may or may not be combined with almetal or metallic salt such as copper, lead,

zinc, iro orother metal having an lafiinity for the iilp'hur compoundsof the oil, such as described in Patent No. 1,515,733 of N0- .vember 18,1924, to Roy Cross. Where the oil has a high sulphur content, thetreatment is much more elfective Where the metallic mineral is used withthe clay. This clay. or adsorbent aluminum silicious matter isintroduced to the agitator by means of a hopper 27 and a conveyor screw28 drivenl by means of a motor 29. The amount of clay or silica usedwill vary according to the character of the oil and the amount' of acidnecessary for proper treatment. It will -be noted that there is no waterwash between the acid treatment and the treatment with the adsorbentclay or bentonite.

In order t0 produce the desired turbulency `and intimate mixture of theclay and oil, a circulatory system consisting 0f pipes 30, 3l and acentrifugal pump 32, are supplied in order to circulate the mixture toand from the agitator. From time to time quantities of the mixture aredrawn olf through the pipe 33 regulated by a valve 34 and directed to afilter press diagrammatically shown at 3 5. In the filter press the clayis separated from the treated liquid oil, the oil passing off' throughthe line 3 6 controlled by a valve 3 7, While the clay is removed-fromthe filter cloths or screens and-reignited when it is ready for reuse inthe agitator. By means lof this system, a relatively short and completecontact-say, of one-half minute duration-of the acid and oil may beproduced,the rapidity of contact eliminating, to a great extent,polymerization of the gasoline'which considerably diminishes theundesirable eHect of the acid treatment.v For like reasons, the WaterWash has been dispensed with and also for the fact that the addition ofWater tends` to produce a hydrat.

- ing redissolving of certain of the resinous compounds of the oil. Thecentrifuge may be put in a horizontal position.

By utilizing a quick acid treatment and a subsequent effective adsorbentclay treatment, a distillate oilfor untreated gasoline,`

kerosene or the like, may be purified to a degree that it Will pass thecommercial tests for marketable motor fuel. yThis treatment, also, doesnot affect the boiling point range as do redistillation treat-mentsheretofore deemed necessary in the -refining of commercial motor fuelcommonly known as gasoline.

`During ythe period of acid contact, it is highly desirable that thetemperature of both oil and acid bekept as low as is'practicallypossible and at all times below 100 F. To advantageously maintain thistemperature, parts of the apparatus may be suitably water-cooled, suchas the centrifuge and related parts, or the oil may be chilled prior toits introduction to the system. f

' I claim as my invention:

1. A continuous process for treating petroleum hydrocarbons, consistingin combining the oil with an acid to form an intimate mixture, limitingthe period of contact to a predetermined length of time of approxi-4mately one half minute to prevent polymerization of the oil, separatingthe oil from the acid sludge by mechanical separation.

2. A continuous process for treating petroleum hydrocarbons, consistingin combining the oil With-an acid to form an intimate mixture, .limitingthe period ofcontact to a predetermined length of time of approximatelyone half minute to prevent polymeri. zation of the oil, Separating theoil from the acid sludge by centrifuging. I

3., An apparatus for purifying oil comprising a homogenizer, a conduitconnected to f' the homogenizer and provided With baille means in theconduit, means connected to the conduit adapted to separate the oil fromthe acid body.

WALTER 'M. CROSS.

